Bump net-imap from 0.3.4 to 0.3.7

Bumps [net-imap](https://github.com/ruby/net-imap) from 0.3.4 to 0.3.7.
- [Release notes](https://github.com/ruby/net-imap/releases)
- [Commits](ruby/net-imap@v0.3.4...v0.3.7)

---
updated-dependencies:
- dependency-name: net-imap
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Gemfile.lock

@@ -262,7 +262,7 @@ GEM
     mini_portile2 (2.8.2)
     minitest (5.18.0)
     multi_json (1.15.0)
-    net-imap (0.3.4)
+    net-imap (0.3.7)
       date
       net-protocol
     net-pop (0.1.2)
@@ -433,7 +433,7 @@ GEM
       concurrent-ruby (~> 1.0)
     thor (1.2.2)
     tilt (2.2.0)
-    timeout (0.3.2)
+    timeout (0.4.0)
     timers (4.3.5)
     traces (0.9.1)
     tzinfo (2.0.6)